Hydrogen Storage in Mesoporous Molecular Sieves and Pillared Clays

2 Hydrogen Storage in Mesoporous Molecular Sieves and Pillared Clays 

The consideration given to the family of MMS adsorbents is mostly as a consequence of the unique ordered mesopore structure, which is not shared by other families of adsorbents [2], Additionally, with regard to the pore structure, one of the most exceptional characteristics of these materials is the large BET surface area, usually in the range between 600 and 1300m2/g and pore volume generally greater than 0.6 cm3/g. 

In the case of pillared clays (PILCs), notwithstanding the fact that these materials were initially developed as catalysts, there have also been other investigations, where PILCs have been studied as potential sorbents, especially for gas separation applications. These materials have a developed micropore structure with a relatively large BET surface area, normally between 300 and 400m2/g and a micropore volume around 0.15 cm3/g [154,155], 

In this regard, as a result of their adsorption properties, MMS and PILCs could be convenient materials for hydrogen storage. But, there are very few reports on hydrogen adsorption in MMS [156] and pillared clays [9,157], 

The obtained experimental results indicate that the hydrogen uptake at 77 K and 0.1 MPa in the silica mesoporous molecular sieve, MCM-41, is very low [147], Nevertheless, MMS have been used as templates for the creation of ordered porous carbon with tailored pore sizes, which can be applied in hydrogen storage [158], 

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